Seventy-five fresh autopsy specimens were carefully studied and analyzed relative to the relationship between the arcuate ligament of the diaphragm and the celiac artery, the celiac plexus, and the inferior phrenic arteries. The following observations were made: (1) that the celiac ganglionic cuirass often participates in arterial compression, (2) that the celiac artery origin was at or above the median arcuate ligament in up to 25 (33%), (3) that this was due to a low ligament rather than a high artery, and (4) that it is more common in mesomorphs and endomorphs and in females. The ligament was exceedingly variable in character. Autonomic nerves were found closely associated with it.